Skip to main content

Full text of "Woodworking"

See other formats

Ball Clock 

Make [Projects 

build, hack, tweak, share, discover, J 

Ball Clock 

Written By: Steve Lodefink 


Wood block (1) 

4 1/2"x4 1/4"x2" block of wood for the central hub, or the body of the clock. 

Dowel (4) 

36"x1/4" hardwood dowels. 

Wood balls (12) 
2" hardwood balls. 

Quatrz clock movement (1) 
3/4" shaft quartz movement. 

Clock hands kit (1) 

Epoxy cement (1) 

Thin sheet metal (1) 

or basla wood for oversized clock hands. 

Flat black spray paint (1) 

Sandpaper (1) 

220-grit and 400-grit sandpaper. 


The George Nelson ball clock is a neat little slice of mid-century art and architecture, but 

© Make Projects 

Page 1 of 7 

Ball Clock 

with the current licensed reproduction selling for around $265, I decided that if I were going 
to have one, it would have to be an unofficial version. 

I made my first ball clock as an exercise in learning how to use a MIG welder, and ended up 
with a double-sized, welded-steel version of the clock. I was excited when asked to write 
this how-to piece, but realizing that most people probably don't have access to welding 
equipment, I decided to create a new ball clock that could be put together with all wood parts 
and assembled Tinkertoy style. 

Conveniently, I found that I was able to gather up all the supplies for the clock with a single 
stop at a Rockier woodworking store, or a session on their website ( ). 

Use a compass to mark a 4 1 /2" circle onto the wood block. Use a jigsaw or band saw to cut 
out the circle. You should make radial "relief" cuts before cutting out the circle; this will 
prevent the blade from binding and burning the wood, and allow it to turn a tight corner. 
Next, use a belt or disc sander to remove any cutting marks, square up the hub, and make 
it smooth and round. 

© Make Projects 

Page 2 of 7 

Ball Clock 

Drilling the holes for the radial spokes is the most critical part of this project. If the holes 
aren't all on the same plane and drilled directly toward the center of the hub, the clock wi 
look catawampus. 

First, drill a 1/4" hole through the center of the clock. Next, scribe a line all the way around 
the outside of the hub, centered edge-to-edge. Using a protractor, make a mark every 30 
degrees around the face, to make 12 evenly spaced marks. Transfer these marks down to 
intersect the line, and mark for drilling. Use a drill press to drill each radial hole 11/2" deep, 
aligning the drill directly toward the center hole. 

© Make Projects 

Page 3 of 7 

Ball Clock 

• While you've got the 1/4" drill bit in 
the chuck, drill a 1" deep hole in 
each of the 2" wooden balls. 
Typically, there will be a little flat 
spot on one side of each ball; this 
makes a great spot to drill the hole. 
Take care to drill straight into the 
center of the ball. 

• Next, use a fine-toothed saw to cut 
the 1/4" hardwood dowels into 
twelve 12" lengths. Lightly sand the 
cut ends of each spoke. 

• If you prefer to stay truer to the 
original design, you can make the 
spokes from 1/4" brass tubing, 
available at hardware and hobby 
supply stores. 

Remove the locking nut and washers from the movement and insert the center shaft into 
the hole in your wooden clock hub. 

With a pencil, trace around the movement's case onto the hub. Draw the outline of the 
movement 1/4" or so larger than it needs to be, to make fitting the movement easier. I used 
a router with a straight-cutting bit to excavate the recess for the clock movement, but you 
could also use a drill with a Forstner bit, and then square up the corners with a wood 
chisel. Cut the recess to a depth of 1 W, which will leave you with a 3/4" floor. Test-fit the 
movement to make sure that there is enough shaft exposed to thread on the lock nut. 
Deepen the recess if necessary. 

© Make Projects 

Page 4 of 7 

Ball Clock 

To recreate the whimsical, oversized hands of the original Nelson clock, I started with a 
handset that was specifically made to work with the movement that I was using, and then 
augmented the stock hands with some oversized cutouts. 

Balsa wood or thin sheet metal are ideal choices for a hand material, because they are 
thin, light- weight, and fairly rigid. The finished hands need to be light, or the somewhat 
anemic quartz movement won't be able to swing them around the clock dial. I cut the oval, 
triangle, and rectangle shapes for my new hands from a scrap piece of light-gauge 
aluminum dryer duct that I had lying around the shop. Mix up some epoxy, and cement the 
new hands in place over the old hands of the clock. Use something heavy to press the 
hands flat while the cement dries, and use waxed paper to keep the cement from sticking 
to your work surface. Once the glue dries, use an X-Acto knife to reopen the holes where 
the hands mount onto the center shaft of the movement. 

Paint the hands with a few light coats of flat black spray paint. Flat black will help hide any 
imperfections in thin sheet-metal hands. If you make your hands from balsa wood, lightly 
sand the top surfaces with 400-grit sandpaper between coats of paint. 

© Make Projects Page 5 of 7 

Ball Clock 

Sand all wood parts with 220-grit, then 400-grit sandpaper. I made my clock body from a 
beautiful Mexican hardwood called bocote, which has a really nice natural color and figure, 
so I chose to finish the wood with a simple oil finish. I was happy with the color of the 
walnut spokes, so they received a coat of oil and wax too. If you plan to use a stain, 
varnish, or polyurethane topcoat on any of your wood components, apply it now. I gave the 
maple balls two coats of clear, non-yellowing acrylic lacquer. 

Put a small amount of wood glue on the ends of the dowels before inserting them into the 
balls. Then press each ball/spoke pair into a hole in the hub, again using a small drop of 
wood glue. 

Install the clock movement, securing it with its locknut. Install the hands, and thread on the 
little nut that holds them in place. Check that the hands don't interfere with each other as 
they move, bending them slightly to make adjustments if necessary. 

I was able to mount my clock by simply hanging it on a nail, using the clock movement 
recess itself as a hanger, but if you want a more secure mounting, you could add one of 
those sawtooth picture hangers to the back of the clock. Or, drill a 1/4" hole in the back of 
the clock hub to use as a mounting point. 

Now you've got what is, in my opinion, better than an original Nelson clock. Not only does 
it have an accurate quartz movement that doesn't need a plug, but you get to fine-tune the 
size and finish to suit your needs. 

Meanwhile, back at the ranch, you've got the perfect clock for that timeless spot. 

© Make Projects 

Page 6 of 7 

Ball Clock 

This project first appeared in CRAFT Volume 01 , pages 135-137. 

This document was last generated on 201 2-1 1 -02 1 1 :00:33 PM. 

© Make Projects Page 7 of 7